The United Nations Security Council “strongly condemned” North Korea’s nuclear test carried out earlier Tuesday and committed to responding swiftly to the North’s “clear threat to international peace and security” with a new round of sanctions targeting the isolated regime’s nuclear and missile programs.

Pyongyang’s third and apparently most powerful nuclear test may have been designed in part to convince the domestic North Korean audience of the young leader Kim Jong-un’s hold on power. But it also succeeded in further uniting the international community – notably including China – in opposition to the North’s actions.

US Ambassador Susan Rice, speaking at the UN after the Security Council’s condemnation, said the unanimous action indicates the 15-member body “will deliver a swift and credible response.”

Noting that already in January the council had committed to “significant action” if the North proceeded with another nuclear test, Ambassador Rice said the North’s “highly provocative” action meant that, “indeed, we will do so.”

It could still be a matter of weeks before the council comes up with a resolution whose measures could include everything from travel bans on officials involved in the North’s weapons programs to even stricter inspections of North Korean vessels and financial sanctions, regional experts say. During that time all eyes will be on China to see how far Beijing, increasingly exasperated with its troublesome ally and neighbor, is willing to go to punish the North for its actions.

The North’s underground test, its third nuclear explosion in six years, set off the first international crisis of President Obama’s second term and served as a stark reminder that North Korea – and the nuclear proliferation risks and regional destabilization it threatens – is not going to fall far from the top of the president’s international priority list.

As usual, Pyongyang had two audiences in mind, regional analysts say, as it proceeded with a test that it had been warned by world powers – including the US and China – not to carry out: the regime’s domestic audience, and the international community, headed by the US.

Mr. Kim, in power for just a year, is still establishing his credentials with the country’s military leaders, experts say, and is also letting the North Korean population know that he is a strong leader in the tradition of his father and grandfather.

The North is also acting to convince the world – and in particular the US – that it is now a full-fledged nuclear power that can threaten others as much as it is threatened by them. That the regime in Pyongyang chose the day of Obama’s State of the Union address to conduct its test is an indicator of how much the test was meant as a message for the US, regional analysts say.

That the test was carried out while South Korea holds the month-long revolving presidency of the UN Security Council virtually guaranteed a swift international response. South Korean Foreign Minister Kim Sung-hwan told reporters in New York after the council meeting that, while the North may have chosen to act while South Korea presides over the Security Council, the council’s “strong condemnation” of the test was a message to the North that a united international community would “hold it responsible” for its “provocative act.”

China, which is the impoverished and repressive North Korea’s lifeline and only major ally, went along with the US last month on tightening existing sanctions after the North carried out a long-range ballistic missile test.

On Tuesday Beijing summoned the North Korean ambassador to the Foreign Ministry to protest, and Chinese Foreign Minister Yang Jiechi announced that China was “strongly dissatisfied and resolutely opposed” to the nuclear test and urged the North to cease its destabilizing actions and to return to “dialogue” with the international community.

At the UN, Rice said the US was awaiting further information on the “technical specifications” of Tuesday’s blast. But nuclear experts said it may have been the North’s first test of a uranium-fueled (rather than plutonium) device – a development that would have worrisome implications for the North’s potential as a security threat and as a proliferator of nuclear weapons.

Calling such a development a “game-changer,” former UN nuclear adviser and now Notre Dame University Professor George Lopez says a uranium explosion would suggest the North’s ability to both “produce and export” a uranium-fueled device – a development that would pose urgent new questions about North Korea’s cooperation with Iran in its nuclear program.

A uranium-fueled device would pose additional concerns because uranium enrichment can be carried out in a smaller space than is required by plutonium and thus is more easily hidden, nuclear experts say.

China will be deeply concerned about these developments on its border, Professor Lopez notes, but he adds that Beijing will continue to discourage any blunt economic reprisals that could destabilize the regime in Pyongyang and thus destabilize the region.

As a result, Lopez says he anticipates the Security Council coming up with a resolution whose measures focus on limiting both the North’s access to the materials and parts it needs to continue developing its nuclear program – and its ability to export its technology to others.